Carbureter.



. This invention relates to ALFRED C. STEWART, DE LOS ANGELES, CALIFQRNIA.

. oAnBUnE'rEnQ resents.

Specification of Letters Patent.

Patented am a, ram.

Application filed November 11, 1914. Serial No. stasis.

To all whom it may concern:

Be it known that I, ALFRED C. STEWART, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Carbureter, of which the following is a specification.

a carburetor of the type wherein the liquid fuel is supplied to the carbureting means from a fuel chamber in which a definite level of fuel is maintained by float-operated valve means, and

the valve' member 9 extending over said reone object of the invention is to provide im- .proved means for temporarily opening such valve to flush the carbureter.

Another object of the invention is to provide for retaining the float controlled valve in closed position, to revent leakage therethrough, when the car ureter is not in use.

Another object of the invention is to provide im roved means for regulating the supply of el to the carburetor.

The accompanying drawings illustrate my invention, and referring thereto:

Figure 1 is a side elevation of reter.

Fig; 2 is a vertlcal sectlon thereof.

Fig. 3 is a section on ,line ww in Fig. 2.

Fig. 4 is a side elevation of the controlling means for the fuel regulating valve.

The carbureter" comprises a casing formed with a fuel chamber 1 and a mixing chamber 2, separated by a partition member 3, which is shown as provided with an annular'screwthreaded flange 4 on which the members 1 and 2 are screwed. Thefuel chamber 1 is formed as a cup, closed at the bottom. The mixing chamber 2 is shown as provided with e a jacket or outer wall 6 having a screw portion screwed on the flan e 4. Said mim'ng the carbuchamber is further provided with an inner wall 2 whose lower face engages the partition member 3'to make a tight joint; The space 6' between the outer and inner walls of the mixing chamber serves asa jacket space for receiving hot water or other heating medium, in case a heavy oil is used for fuel; suitable connections 5 and 5' being provided for circulationof such medium through said space. Mixing-chamber 2 is provided with air inlet means 8, consisting for example of a funnel shaped member screwed into the top of chamber 2 and open at its upper end to the outer air, and communicating at its lower end, through an inlet valve opening 8., with the mixing chamber 2. Said mim ng chamber, is provided with outlet means 7 having a throttle 7 A valve 9 is mounted by its stem 10 to move vertically within the mixing chamber to close oropen the air inlet opening 8, s'aidvalve-stem sliding in a tubular guide 11 on' the partition 'member 3, and carryin at its lower end a piston 12, working within a cylindrical wall 13 in the fuel chamber 1, forming 'a' dash pot. carries a fuel receiver or spreader 15, having an annular inclined outer wall or lip 15,

ceiver or spreader and sufiiciently spaced from said lip to form a narrow annular out- 7 let passage 16 from thespace 14 between said valve member and spreaderto the mixing chamber. This space 14: in the valve device communicates through openings 18 in the and it also communicatesthrough openings 19,'with a passage 20 in the valve stem 10, said passage 20 communicating through openings 21 in the stem and openings 22:- in the hub 22 of the dash pot piston, with rthe interior of the fuel chamber. A spring 24,

Valve stem 10 also valve 9,. with the outer air above the valve; I

extending between members .3 and 15, tends to hold valve 9 to closed position.

-A float 25' within the fuel chamber 1, is guided by a sleeve 25"thereon, slidable on a portion 26 of the valve stem, saidfloat engaging a lever 27 pivoted at 28 on'the casing and havin a portion 29 engaging a valve pin 30, which works within a bore 31 in the wall 2' of the mixing chamber and is tapered at its upper end to cooperate with a valve seat 32 formed at the lower end of a tube 33 screwed into an enlarged extension of said bore.- The fuel supply pipe is connected to this tube 33, the opening 32 of valve seat 32,

otherwise, so as to allow fuel to flow past the body of the pin when'th'e val'veis open.

Valve stem 10-is provided with a shoulder 36 ada ted to engage the sleeve 25' of the float to fbrcibly depress the float when the air inlet valve 9 is fully opened, therebyprovidmay close or obstruct the passages or open lugs 19 leading to the receiver or spreader 15. This taper pin'is preferably adjustable,

being pressed upwardly by a spring '40 and depressed more or less, according to'requirements, by helical cam means 41 on a vertically slidable and rotatable pin 42 carrying an operating lever 43, having suitable operating connections, not shown, said cam means 41 engaging a cam means 45formed as a screw member screwing in a spider 46 on the air inlet member' 81. Pin 38'has a shoulder 47, adapted to engage a tubular extension 48 on valve 9, to depress said valve.

The operation is as'follows: Normally, or when the device is not in use, the valve 9 is held in raised position, as indicated by dotted lines in Fig. 2, said valve being then within the air inlet opening 8 and cooperating' with the seat surrounding 'said opening to closethe same. At the same time the fuel inlet 32 is closed by a valve pin 30 which is held closed by the force of the main valve spring 24 as above stated. When the engine is started and throttle 7 is opened, a condition of suction or partial vacuum is produced in the mixing chamber at each 'suction stroke of the engine to which the carbureter is connected by its outlet 7, and the valve 9 is thereby drawn down so as to open the air inlet 'air'then passing from said air inlet, pastt e edge of the valve 9;, to the mixing chamber. The condition of suction in the mixing chamber is communicated through the annular outlet opening 16 to the space 14 within the. valve device, with the result that fuel is drawn from the fuel chamber through passages 22, 20 and 19 to the receiver or spreader 15-, and also with the result that air is drawn through openings 18 in valve 9 to said space 14 above the receiver. or spreader, and this air, passing at high velocity over the fuel in the receiver or spreader, carries the same forward and violently. ejects it through the annular outlet in the form of a sheet or spray of mixed fuel and air. This sheet or spray of air and fuel meets the current of air passing the edge of valve 9 at high velocity, from the air inlet to the mixing chamber, and is efi'ectively mixed and vaporized by'.the action of the impinging air currents. It will be noted that t e spring 24 resists the opening of valve 9;, under the action of'the suction inthe mixing chamber, thereby insuring the production of a strong vacuum in the mixing chamber, suficient to produce the required suction of air and fuel, and as acceleration. The action of the spring 24 and the dash pot, in producing an extra high vacuum1when the throttle is first opened gives a rich mixture in starting. If, however, it is desired to flush the carbureter to increase still further the richness of the mixture in starting, or at any time when extra acceleration is required, the controlling pin 42 is moved by its lever'43, so as to force the pin down by action of cams 41, 45 and thereby depress the pin 38 until the shoulder 47 thereon engages the top of extension 48 of valve 9 and forces valve stem 10 down, bringing shoulder 36 thereon against float member 25, whereupon the float lever 27 is depressed so that valve 30 opens and allows an extra quantity of fuel to flow to the fuel chamber, thereby flushing said chamber, and producing the'requlred increase of fuel supply, with consequent increase of power. It will be noted that the valve may be opened in this manner irrespe'ctive of the level of the fuel in the fuel chamber, and therefore it is possible by this means to raise the fuel above the maxlmum level required under normal running conditions. a

By arranging the fioat in the fuel chamber around the valve stem and over the piston thereon, and utilizing the said valve stem as a guide for the float, l utilize the space ofiered by the valve and dash pot construction for the operation of the float, thereby making the device extremely compact. Moreover, the operation of the valve, under normal running conditions, leaves the float free to perform its usual functions, and only limits or controls the motion thereof, at the limits of motion of the valve, as above stated.

What I claim is:

1.. In a carbureter, a fuel chamber provided with a fuel inlet valve, a float in said chamber to close said valve when the fuel reaches a definite level in said chamber, a mixing chamber, an air inlet valve therefor, and means connected with said air inlet valve for forcibly opening said fuel inlet valve.

2. ln a carbureter, afuel chamber provided with a float-controlled fuel inlet valve, a mixing chamber, an air inlet valve therefor adapted to open under the suction in temporary increase in the suction which increases the fuel supply and gives more rapid said mixing chamber, and provided with means tending to move it to closed position,

a controlling device for forcibly moving" said air inlet valve to open position, and means operated by said air inlet valve for opening said fuel inlet valve.

3. In a carbureter, a fuel chamber provided with an inlet valve, a float in said chamber adapted to close said valve when the float rises, spring operated means supplementing the action of the float, for forcibly holding the inlet valve closed and means operated by suction in the carbureter for acting on said spring operated means to nullify the action-thereof on said fuel valve.

4; In a carbureter, a fuel chamber provided with a fuel inlet valve, a float for closing said valve when the fuel in the chamber reaches a definite level, spring operated means for forcibly operating said float to close said valve and manually operated means for acting on said spring operated means to relieve the fuel valve from the action thereof and for acting on said float to cause said valve to open irrespective of the level of the fuel in the fuel chamber. 7

5. In a carbureter, a fuel chamber provided with a float-controlled fuel inlet valve, a mixing chamber provided with a springcontrolled air-inlet valve, and means operated by said air inlet valve to close said fuel inlet valve when the air inlet valve is closed.

6. In a carbureter, a fuel chamber provided with a fuel inlet valve and with a float for closing the same, a mixing chamber provided with an air inlet valve, a spring for closing said air inlet valve, and means connected to said air inlet valve-to raise the float and hold the fuel inlet valve closed, when the air inlet valve is closed.

In testimony whereof I have'hereunto set my hand, at Los Angeles, California, this 30th day of October, 1914. v

ALFRED O. STEWART.

Witnesses:

A. P. KNIGHT, Oscar: E. WINBURN. 

